SELECT epc.class_id ,COUNT(ep.id) as count,lcy.experiment_plan_id labClassYearId FROM school_experiment_plan ep LEFT JOIN school_experiment_plan_class epc on ep.id=epc.experiment_plan_id
left join school_lab_class_year lcy on lcy.experiment_plan_id = ep.id
WHERE ep.del_flag=0 and epc.del_flag=0 AND ep.school_year = #{schoolYear} AND ep.semester=#{semester}